The U.S. gained a whopping 312,000 new jobs in December to bring total employment gains in 2018 to a three-year high of 2.64 million. Economists polled by MarketWatch had expected a gain of 182,000 nonfarm jobs. The unemployment rate rose to 3.9% from a 49-year low of 3.7%, largely because more people entered the workforce in search of jobs.